Studies will be on human transitional cell tumors (TCT) of the genitourinary tract. To support these investigations, a tumor and serum bank was established. Storage and retrieval are controlled by computer. We will continue to add to this bank during these studies. TCT's have been grown long term in tissue cultures and cell lines were established from both primary and metastatic TCT. Certain cell lines have been in culture over nine months. We will expand our tissue culture facilities so as to produce the tumor cells needed in these studies. TCT's were studied by both virological and immunological techniques. An RNA virus was isolated from the primary cell cultures of these tumors. This virus resembles known animal RNA tumor viruses as described herein. The virus is being produced by infecting susceptible cells (HEK, CEF, etc). More virus is needed: (1) to determine biochemical nature of viral proteins; (2) to determine species of viral 'core' RNA; (3) for nucleic acid hybridization studies; (4) to investigate immunology of virus antigens; (5) for both in vivo and in vitro studies of its oncogenic potential; and (6) for precise identification studies. This virus will be studied intensively relative to (1) oncogenic potential; (2) precise identity; and (3) macromolecular characteristics. Thus, much of our expanded program will be directed toward producing more virus for macromolecular, immunological and transformation studies. More detailed morphological studies are planned.